The Alexandria, Va., federal courthouse. (Gerald Martineau/The Washington Post)

Four days after a high school junior says a senior boy forced her to engage in sexual activity under a blanket on a band trip to Indianapolis, her principal at Oakton High joked about the incident.

Asked by a vice principal on the trip how many “inches” the school might get from snow that March 2017 week, he replied in an email, “How many inches under the blanket or on the ground?”

In a text to the same vice principal, a school police officer described the alleged sexual assault by referencing the teen sex comedy “American Pie.”

Now, a jury in Alexandria federal court will decide whether the school’s reaction was so cavalier as to violate the girl’s civil rights under Title IX. She filed a lawsuit against the Fairfax County School Board last year after what she described in court as an offensive and inadequate response after a boy put her hand on his genitals and his hands under her shirt and down her pants, penetrating her with his fingers. She was 16 at the time; he was 18.

“It was one thing to be assaulted; it’s another thing for the people who are supposed to protect you to do nothing, not just do nothing, but to blame you for it,” the girl testified. “I think if something like this happened to me again, I would have a hard time reporting it.”

The girl, who says she suffered physical and mental distress because of the school’s response, is asking for unspecified financial damages.

Fairfax has been operating under an agreement with the Justice Department since 2014 to improve its handling of sexual harassment. The case is one of three active lawsuits in the Eastern District of Virginia against the county school board under Title IX, which bars sex discrimination in schools that receive federal money.

The Washington Post is not identifying the alleged victim of the sexual assault or the alleged perpetrator, who was not charged with a crime.

The girl testified that when she was called in to speak to administrators after the trip, they asked “accusatory questions” about her clothing and behavior.

School officials told jurors that they asked questions to figure out what had happened and that what they learned made it impossible to describe the situation as assault: The girl agreed to sit with the boy, shared her blanket with him, wore his hat and leaned her head on his shoulder, they emphasized in testimony. She did not verbally reject him, and by her own account continued touching his genitals for about a minute after he took his hand off hers. She did not try to change seats during or after the alleged assault.

“It’s a gray area,” defense attorney Sona Rewari told jurors in her closing argument Wednesday. “Do you have to say yes or do you have to say no. . . . She had not said anything.”

She argued that the girl began describing the sex act as forced only after learning she might get in trouble and that the boy had a girlfriend.

The girl testified she “did the best that I could to try to get away from him” but was too “embarrassed” to call attention to herself on the charter bus. “I didn’t know how to handle it,” she said. “I had never had a sexual experience in my life before. I was just really shocked and scared.”

Two friends testified the girl had confided in them before learning the boy had a girlfriend; three more spoke to her later in the trip. All said the girl was clear that what happened was not consensual.

“The only people who didn’t see this as prompting a . . . serious response were the [school officials] who were tasked to do just that,” plaintiff’s attorney Lauren Khouri said in closing.

A fellow student and friend of the girl, who was back in Fairfax, got a call from her the night of the bus trip. The next day, he went to his math teacher, who reported to school security what the teacher testified was an alleged sexual assault.

But after talking to the student, the school resource officer, Darrell Estess, texted assistant principal Michelle Taylor that he had been told of a “sexual act” on the trip she was helping lead, adding a joking reference to the movie “American Pie.” Estess did not testify at the trial but in a deposition in the case said the incident occurred outside his jurisdiction.

Another student, who spoke to the girl the morning after the bus ride, went to the band director, who texted Taylor that the boy had apparently “put himself on” the girl and that she “wasn’t into it.” Taylor, who now works at James Madison High School, spoke to the girl herself but testified the conversation did not include the words “sexual assault.”

Taylor called Principal John Banbury, who testified that he was left with the impression a “hookup” occurred. He told Taylor to keep an eye on the girl but otherwise wait until the five-day trip was over to act. When she asked him to predict that week’s snowfall, he replied with the joke about “inches.”

Banbury testified that while his comment was “inappropriate” and “unprofessional,” he “was not mocking . . . sexual harassment.”

When the band returned to Virginia, another of the girl’s friends told her mother about the alleged assault. The friend’s mother contacted Taylor, calling the matter “urgent.”

It was at that point that officials began to view the incident as serious.

The “potential issue on the band trip,” Taylor wrote to two other administrators, was “apparently . . . an actual issue.” Director of student services Jennifer Hogan was chosen to deal with the situation because of her counseling background.

After speaking with the girl and the boy, Hogan testified, “there was nothing to show that it was a sexual assault.” The boy, she said, “was stunned that he was being accused of this.”

She said he “spilled out all the details,” including ones the girl left out of her first interview: that she agreed to sit next to him, shared her blanket and wore his hat.

While Hogan described the boy as credible, at trial he admitted he changed his story several times, though he has always maintained the encounter was consensual. He testified that he never touched the girl’s breasts or genitals, explaining that he had earlier told Hogan he had done so “just to get out of there.” He testified he could not remember if the girl tried to block his contact.

Hogan said she believed the girl “was stuck in a situation and didn’t know how to get out of it but participated” and that the girl needed help learning to “advocate for herself.”

The school did not keep copies of statements signed by the girl, the boy and two witnesses as well as notes taken by and texts exchanged between school officials. Banbury said he did not review the statements before declining to take any action.

No one was disciplined.

Attorneys for Fairfax challenged the girl’s claims of emotional distress, noting her grades improved after the incident and that her teachers saw her as functioning well.

The girl and her parents testified they were left with the impression that she could be punished and were warned against taking legal action, which officials denied. Hogan said she considered disciplining only the boy but decided it would be unfair, instead telling him to “next time get verbal confirmation.”